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    <title>Document</title>
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<script>
    // 写一个函数，能翻转传入的任意数组，并把翻转结果通过返回值返回

    function reverse(arr = []) {
        let newArr = [];
        for (let i = arr.length - 1; i >= 0; i--) {
            newArr[newArr.length] = arr[i];
        }
        return newArr;
    }

    console.log(reverse([2,1,3,5,4]));
</script>
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